Betula Pendula

I have some silver birches that I planted about two and a half years ago, two betula pendula and two jacqumontii. Very suddenly, one of the pendulas has started turning yellow - almost every leaf - looks like autumn! The others are all ok. It had been very lush and green up to a couple of weeks ago. I have watered during very dry spells and fed with a little growmore.

Does anyone have any idea what could have caused this?

Thanks

Ann

 

Any chance of a picture, Ann?:gnthb:

 

Something like that occured two years ago to my Birch-tree.
In August, the leaves started getting yellow with some small black spots.
They told me that it was due to a "fungus". They suggest me a product to water-dilute and to directly spray on the leaves.
I do not know whether it worked.
I only know that then the autumn came, the leaves fell down and the following spring everything was ok.
So, what's wrong with it ??? Just wait for the autumn... :wink:

 

Some pics of the tree and close ups of the leaves would be appreciated, silver1. Then perhaps we can see what the problem may be.